error_t iohelp_restrict_iouser (struct iouser **new_user, const struct iouser *old_user, const uid_t *uids, int nuids, const gid_t *gids, int ngids) { if (idvec_contains (old_user->uids, 0)) /* OLD_USER has root access, and so may use any ids. */ return iohelp_create_complex_iouser (new_user, uids, nuids, gids, ngids); else { struct idvec *uvec, *gvec; int i; error_t err; uvec = make_idvec (); if (! uvec) return ENOMEM; gvec = make_idvec (); if (! gvec) { idvec_free (uvec); return ENOMEM; } /* Otherwise, use any of the requested ids that OLD_USER already has. */ for (i = 0; i < old_user->uids->num; i++) if (listmember (uids, old_user->uids->ids[i], nuids)) { err = idvec_add (uvec, old_user->uids->ids[i]); if (err) goto out; } for (i = 0; i < old_user->gids->num; i++) if (listmember (gids, old_user->gids->ids[i], ngids)) { err = idvec_add (gvec, old_user->gids->ids[i]); if (err) goto out; } err = iohelp_create_iouser (new_user, uvec, gvec); if (err) { out: idvec_free (uvec); idvec_free (gvec); } return err; } }
/* If IDVEC doesn't contain ID, add it onto the end, returning ENOMEM if there's not enough memory; otherwise, do nothing. */ error_t idvec_add_new (struct idvec *idvec, uid_t id) { if (idvec_contains (idvec, id)) return 0; else return idvec_add (idvec, id); }
kern_return_t trivfs_S_io_restrict_auth (struct trivfs_protid *cred, mach_port_t reply, mach_msg_type_name_t replytype, mach_port_t *newport, mach_msg_type_name_t *newporttype, uid_t *uids, size_t nuids, uid_t *gids, size_t ngids) { int i; error_t err; struct trivfs_protid *newcred; struct idvec *uvec, *gvec; struct iouser *user; if (!cred) return EOPNOTSUPP; if (cred->isroot) /* CRED has root access, and so may use any ids. */ { err = iohelp_create_complex_iouser (&user, uids, nuids, gids, ngids); if (err) return err; } else { uvec = make_idvec (); if (! uvec) return ENOMEM; gvec = make_idvec (); if (! gvec) { idvec_free (uvec); return ENOMEM; } /* Otherwise, use any of the requested ids that CRED already has. */ for (i = 0; i < cred->user->uids->num; i++) if (listmember (uids, cred->user->uids->ids[i], nuids)) { err = idvec_add (uvec, cred->user->uids->ids[i]); if (err) goto out; } for (i = 0; i < cred->user->gids->num; i++) if (listmember (gids, cred->user->gids->ids[i], ngids)) { err = idvec_add (gvec, cred->user->gids->ids[i]); if (err) goto out; } err = iohelp_create_iouser (&user, uvec, gvec); if (err) { out: idvec_free (uvec); idvec_free (gvec); return err; } } err = ports_create_port (cred->po->cntl->protid_class, cred->po->cntl->protid_bucket, sizeof (struct trivfs_protid), &newcred); if (err) { iohelp_free_iouser (user); return err; } newcred->isroot = 0; mutex_lock (&cred->po->cntl->lock); newcred->po = cred->po; newcred->po->refcnt++; mutex_unlock (&cred->po->cntl->lock); if (cred->isroot && idvec_contains (user->uids, 0)) newcred->isroot = 1; newcred->user = user; newcred->hook = cred->hook; err = io_restrict_auth (cred->realnode, &newcred->realnode, user->uids->ids, user->uids->num, user->gids->ids, user->gids->num); if (!err && trivfs_protid_create_hook) { err = (*trivfs_protid_create_hook) (newcred); if (err) mach_port_deallocate (mach_task_self (), newcred->realnode); } if (err) /* Signal that the user destroy hook shouldn't be called on NEWCRED. */ newcred->realnode = MACH_PORT_NULL; else { *newport = ports_get_right (newcred); *newporttype = MACH_MSG_TYPE_MAKE_SEND; } /* This will destroy NEWCRED if we got an error and didn't do the ports_get_right above. */ ports_port_deref (newcred); return 0; }